ered the probability to be great that a ‘‘good’’ teosinte 
could be synthesized by hybridizing corn and Tripsacum 
in experimental cultures, and we have given reasons for 
this. 
The recent evidence is decidedly in favor of the view 
that introgression between corn and teosinte has been 
frequent and that it has been effective in producing in- 
numerable new varieties and forms, both ancient and 
modern. We now consider that this third part of the tri- 
partite theory is almost an established fact. 
It should be clear from the contents of previous papers 
in this series that we consider the tripartite theory to be 
better supported by factual evidence than any other ex- 
planation of the origin of corn proposed up to the present. 
The fact that we are still committed to the tripartite 
theory, however, should not prevent us from consider- 
ing alternative theories and this we shall attempt to do 
objectively, if briefly, in this final paper. 
THE PApyRrescCENT (Semivestidos) THEORY 
This is no more than a slight modification of the pod- 
corn theory. Andres (1) discovered in Argentine maize 
a type which superficially resembles a weak form of pod 
corn. Apparently unaware that Bonvicini (5) in Italy 
had described this character many years earlier and had 
given it the name ‘‘palee sviluppate,’’ Andres called the 
type ‘‘semivestidos’’ and suggested that it, rather than 
pod corn, might be the ancestral form. 
The character has recently been given still a third and 
probably more appropriate name ‘‘papyrescent’’ by Gal- 
inat (10), whose studies show that the glumes of this type 
become soft and papery as they mature. Unlike pod corn, 
which although sometimes monstrous still represents a 
combination of normal characteristics found in other 
grasses, papyrescent is a defect in development which it 
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